Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

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Unsecured Convertible Senior Notes - Unsecured convertible senior notes outstanding (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Aug. 14, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Principal amount	$ 320,030	$ 320,030
Unamortized discount	(4,743)	(6,572)
Total unsecured convertible senior notes, net	315,287	313,458
Stockholders' equity	85,684	23,780	$ (120,752)		$ (109,021)
2023 Unsecured Convertible Senior Notes
Debt Instrument [Line Items]
Principal amount	95,000	95,000		$ 95,000
Unamortized discount	(619)	(1,282)
Total unsecured convertible senior notes, net	94,381	93,718
Fair value of outstanding unsecured convertible senior notes (1)	92,031	87,163
Convertible Debt				$ 90,200
2026 Unsecured Convertible Senior Notes
Debt Instrument [Line Items]
Principal amount	225,030	225,030
Unamortized discount	(4,124)	(5,290)
Total unsecured convertible senior notes, net	220,906	219,740
Fair value of outstanding unsecured convertible senior notes (1)	$ 118,141	$ 171,867
Cumulative effect adjustment \| ASU 2020-06
Debt Instrument [Line Items]
Convertible Debt			75,500
Stockholders' equity			$ (75,474)